Sync ui/events to chromium @ https://codereview.chromium.org/1210203002

ui/events/gesture_detection/gesture_configuration_default.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/events/gesture_detection/gesture_configuration.h"
+
+#include "base/memory/singleton.h"
+#include "ui/gfx/screen.h"
+
+namespace ui {
+namespace {
+class GestureConfigurationDefault : public GestureConfiguration {
+ public:
+  ~GestureConfigurationDefault() override {
+  }
+
+  static GestureConfigurationDefault* GetInstance() {
+    return Singleton<GestureConfigurationDefault>::get();
+  }
+
+ private:
+  GestureConfigurationDefault() {}
+
+  friend struct DefaultSingletonTraits<GestureConfigurationDefault>;
+  DISALLOW_COPY_AND_ASSIGN(GestureConfigurationDefault);
+};
+
+}  // namespace
+
+// Create a GestureConfiguration singleton instance when using Mac.
+GestureConfiguration* GestureConfiguration::GetPlatformSpecificInstance() {
+  return GestureConfigurationDefault::GetInstance();
+}
+
+}  // namespace ui